Only adjustment for the clutch that I know of on any bike is at both ends of the cable. Check the owners manual for the specs, but you should be able to pull the lever in ~1/8 to ~1/4 inch before feeling the resistance of the clutch disengaging. Also, check the cable to see if it's binding, frayed, or lacking lube. If all is in good shape and it's adjusted correctly, but still slips, the plates probably need replaced. Here's a site that explains how it's done fairly well.
Clicky
'05 CBR600F4i
PCIII USB
-1 Front +2 Rear/Speedohealer
Various screens according to my mood
Hindle Hi Mount slip on oval supersport core
K & N air filter
Matris M3 Damper
Vortex Rearsets
BRG Racing 1/5 turn throttle
Pit-Eck undertail and hugger